NAVAIR technical directives, explained

A technical directive (TD) is a document authorized and issued by the Naval Air Systems Command (NAVAIR) that tells maintainers how to inspect or alter the configuration of aircraft, engines, systems, or equipment after the baseline configuration is set. The Naval Aviation Maintenance Program (NAMP), COMNAVAIRFORINST 4790.2E of 28 October 2024, says TDs include all types of changes and bulletins. They carry information that cannot be disseminated satisfactorily by revisions to technical manuals. The governing rule is short: no configuration change is made to naval aviation systems unless a TD directs it. The Naval Air Technical Data and Engineering Service Center (NATEC) controls the assignment of TD numbers.

Changes, bulletins, and TD codes

The NAMP defines the two kinds. A change directs and gives instructions for a change, modification, repositioning, or alteration of material. A bulletin directs a one-time inspection, carries related instructions, and passes on administrative or management information. An interim change has an immediate or urgent action classification and is issued by message.

Each TD type has a two-character numeric TD code, and each TD has a 12 or 13 character identification code. The NAMP's code table includes, for example:

• 50, Airframe Change (AFC) and 74, Airframe Bulletin (AFB)
• 02, Power Plant Change (PPC) and 01, Power Plant Bulletin (PPB)
• 54, Avionics Change (AVC) and 93, Airborne Software Change (ASC)
• 62, Support Equipment Change (SEC) and 99, Age Exploration Bulletin (AEB)

A Department of Defense data item description, DI-SESS-81269B, approved 21 December 2011, sets out what a contractor delivers. A TD provides the authority and instructions to accomplish and record a material change, repositioning, modification, alteration, or inspection of equipment or software. Format follows Appendices A through E of NAVAIR 00-25-300. The description covers aircraft, weapons, equipment, support equipment, trainers, and companion software, but not intelligence processing equipment.

Four action categories and their clocks

The NAMP assigns every TD one of four categories by type, urgency, and purpose:

• Immediate Action. Unsafe conditions that could cause fatal or serious injury or extensive damage. Compliance is due before the next flight, the next use of equipment, or within the next 10 flight hours. Immediate Action Bulletins that restrict flight are called Grounding Bulletins and need special coordination before release.
• Urgent Action. Hazards from combat necessity or unacceptable losses of readiness, with risk acceptable within set limits. The category covers more than 10 flight hours to 36 months.
• Routine Action. Risk acceptable within broad time limits, more than 36 months.
• Record Purpose. Formal changes that document configuration changes the designer incorporated before the TD was issued, kept as the official record in the Technical Directives Reporting System (TDRS).

Equipment is restricted from use when an Immediate, Urgent, or Routine TD is not met by its due date. The clock runs from the date on the TD in NATEC. The Target Completion Date printed on a TD is the issuer's estimate and does not set the local due date. An operational immediate superior in command, such as a carrier air wing (CVW), may defer compliance for combat operational necessity.

How TDs are issued and tracked

NAVAIR 00-25-300 is the guiding instruction for creating, approving, and issuing TDs. Program offices validate and verify each TD under it before issue. The Aircraft Controlling Custodian class desk coordinates fleet verification: at least one fleet activity tests the TD, and the desk confirms that parts, kits, support equipment, technical manuals, manpower, and funding exist.

NATEC keeps the only official NAVAIR master repository of active, superseded, completed, and cancelled TDs, posts approved TDs, and publishes a weekly summary. In a squadron, the Technical Data Manager opens a review checklist for each new TD and stamps controlled copies. The Revision E highlights add a check of TDs posted since the last summary each working day, and say authority to configure or deconfigure comes only through NAVAIR-issued TDs.

Compliance is tracked in TDRS. The NA500C report lists active TDs for each aircraft and engine type. LIST02 shows airframe changes and bulletins not incorporated on an aircraft, and LIST04 shows those incorporated. Status codes include C for complied with, W for work in progress, and D for does not apply, which a Quality Assurance Representative must verify.

How a TD reaches the technical manual

The TD and the manual stay separate documents, and the manual records the link. NAVAIR's MIL-STD-3001-1A, dated 1 December 2016, requires a historical record of applicable TDs in work package manuals. Each entry gives the TD type and number, such as "F/A-18 AFC 126," the TD date, the title with any engineering change proposal (ECP) or Rapid Action Minor Engineering Change (RAMEC) number, and the date the TD's content entered the work package. When a retrofit TD number is assigned but the TD is not yet issued, and the production ECP is approved, the entry is marked "Production coverage only."

Fleet support teams make the update. AMA 2025-12, dated September 17, 2025, has them revise publications under their engineering authority to take in data such as formal TDs. Each change starts as a Joint Deficiency Reporting System (JDRS) Fast Track Technical Publications Deficiency Report (TPDR). The TPDR establishes a Technical Manual Source Data Record, the authorized method of changing a publication.

What to check

• Is the document a change or a bulletin, and which TD code and identification code does it carry?
• Which action category applies, and was the due date counted from the date on the TD in NATEC rather than the Target Completion Date?
• Do the activity's status codes agree with TDRS lists such as LIST02 and LIST04, and was each "does not apply" verified?
• Does the manual's historical record show the TD date and date incorporated, or "Production coverage only"?
• Was any configuration change made without a NAVAIR-issued TD?

Azcuna's TRACE is one offline viewer for S1000D, MIL-STD-3001 XML, and PDF technical manuals. It keeps the source location and the markings of everything it shows and never modifies the source. It was proposed to NAVAIR under Navy SBIR Phase I topic DON26BZ05-NV078, and the proposal was submitted on September 23, 2026.

Sources

1. 1The Naval Aviation Maintenance Program (NAMP), COMNAVAIRFORINST 4790.2E, 28 Oct 2024 · Commander, Naval Air Forces, posted by Naval Air Systems Command
2. 2The Naval Aviation Maintenance Program, COMNAVAIRFORINST 4790.2E Highlights · Naval Air Systems Command
3. 3DI-SESS-81269B, Data Item Description: Technical Directive · EverySpec (approved 21 December 2011)
4. 4MIL-STD-3001-1A (w/Change 1), Preparation of Digital Technical Information for Multi-Output Presentation of Technical Manuals (Part 1 of 8 Parts) · EverySpec (dated 1 December 2016)
5. 5COMNAVAIRFOR Aviation Maintenance Advisory (AMA) 2025-12, Naval Aviation Maintenance Discrepancy Reporting Program (NAMDRP) · COMNAVAIRFOR San Diego, naval message, September 17, 2025

Where this shows up in our work

• TRACE, the offline S1000D and IETM viewer opens S1000D, MIL-STD-3001 and PDF technical manuals on a tablet with every marking intact.
• ELLMENT, the offline LLM for E-2D crews answers a crew's question from the aircraft's own manuals and cites the page, with no network.